Kpop Myth Busting: "Music Core banned lip-syncing." No, they did not.
I think we all have seen fans use the "lip-sync ban“ excuse to try and convince us that certain live performances, which are obviously lipped, are...
www.reddit.com
excellent post from an Exol/NCTzen.
TLDR :
Music Core never banned lip synching. They allow idols to record in their studios during rehearsal or in the waiting room. Thats why the vocals are sometimes different from the original song. They just greatly encourage not lip synching but they can't just ban it cz a lot of groups would just not come with their tight schedules.
The post also talks about how to recognize if an idol sing live or not : try to listen to the environment (clapping, noise from clothing etc...), voice volume and double voice (heavy backtrack on music core on all stages).
